Cushioning device for rotatable components, such as, for example, roof grab handles or sun visors of a vehicle

ABSTRACT

A cushioning device ( 10, 10.1 ) for rotatable components such as, for example, roof grab handles or sun vizors of a vehicle, having an outer rotational sleeve ( 14 ) and an inner rotational part ( 12 ), which are both arranged in a manner such that they can rotate relative to each other about a common axis of rotation ( 16 ) from a first rotational position into a second rotational position, either the inner rotational part ( 12 ) being fixed and the outer rotational sleeve ( 14 ) being rotatable or the outer rotational sleeve being fixed and the inner rotational part being rotatable, is distinguished in that the outer rotational sleeve ( 14 ) has, on its inner contour, an inwardly pointing inner stop ( 20 ), and the inner rotational part ( 12 ) has, on its outer contour, an outwardly pointing counterstop ( 26 ) which consists of soft material, reduction of the inner radius (R: R 1 ) of the inner contour of the outer rotational sleeve ( 14 ) in the region in front of the inner stop ( 20 ) enabling the outer contour of the counterstop ( 26 ) to come increasingly more strongly into contact with the inner wall of the outer rotational sleeve ( 14 ) during rotation from the first into the second position, as a result of which first of all a braking effect is built up, and, when the counterstop ( 26 ) strikes against the inner stop ( 20 ), the soft material of the counterstop ( 26 ) enables a cushioning effect to be produced.

TECHNICAL FIELD

[0001] The present invention relates to a cushioning device forrotatable components, such as, for example, roof grab handles or sunvizors of a vehicle, having an outer rotational sleeve and an innerrotational part, which are both arranged in a manner such that they canrotate relative to each other about a common axis of rotation from afirst rotational position into a second rotational position, either theinner rotational part being fixed and the outer rotational sleeve beingrotatable or the outer rotational sleeve being fixed and the innerrotational part being rotatable.

[0002] Roof grab handles in vehicles are frequently designed as foldinghandles. Folding handles of this type are folded by hand from theinoperative position, i.e. from a position leaning against the rooflining, into a functional position. When let go, these folding handlesautomatically pivot back into the inoperative position.

[0003] Sun shielding vizors are also designed as foldable components.After a brief actuation by hand, said sun shielding vizors automaticallypivot into the functional position. An automatic retracting pivotingmovement can also be carried out when folding them back.

PRIOR ART

[0004] Folding handles having a handle strap are known, said strap, iflet go in the functional position, striking under the effect of itsrestoring spring against the bearing bracket or the roof lining and inthe process causing annoying noises, or over the course of time damageoccurs reducing the functioning ability. Braking devices which damp therestoring movement of the folding handle have therefore been arranged onthe folding handles mentioned at the beginning.

[0005] EP-A-0 569 022 describes a folding handle which is distinguishedin that a braking spring is provided, said spring being arranged tocounteract the restoring spring and in the inoperative positionprecisely compensating for the restoring spring, the inoperativeposition deviating by a safety angle which is substantially smaller thanthe handle angle from the end position in which the handle strap strikesagainst the bearing bracket or the associated installation wall, and thebraking spring being effective only in the region of a braking anglebetween a brake usage position and the end position.

[0006] German utility model G 93 14 645.0 shows a pivoting jointprimarily for components for vehicles, such as pivoting handles,comprising a bearing sleeve, which are connected in a rotationally fixedmanner to a positionally fixed component, for example to a holder, or toa pivotable component, and a bolt which is mounted rotatably in thebearing sleeve and is connected in a rotationally fixed manner to thepivotable component or the positionally fixed component, and a viscositybrake, by means of which a pivoting movement of the parts with respectto one another, which movement is caused by gravitational force or by aspring element, is damped. As the viscosity brake in this case, acircumferential gap which is filled with a medium of high viscosity isformed between the bolt and the bearing sleeve.

[0007] German utility model 296 04 260.9 describes a folding handlewhich is distinguished in that the braking device is designed as arotational damper and has a radial construction with an, in particular,cylindrical housing, a rotational piston which is sealed with respect tothe housing, can be rotated within an annular body and plunges at leastin some regions into the annular space filled with viscous medium, thehousing has a central, continuous recess, within which the axis ofrotation is arranged in some regions, the handle strap or the bolt isconnected in a form-fitting manner to the housing of the braking deviceand the bearing bracket is connected in a form-fitting manner to therotational piston of the braking unit, or vice versa, and the housingand the rotational piston are clipped together with the aid of a ringand annular groove and said housing and piston form a unit.

SUMMARY OF THE INVENTION

[0008] Starting from the prior art which has been mentioned, the presentinvention is based on the technical problem or object of specifying acushioning device for rotatable components, which device shows acushioning effect and a braking effect, is constructed from few parts,makes economic production possible and ensures reliable functioning inthe long term.

[0009] The cushioning device according to the invention is given by thefeatures of independent claim 1. An alternative cushioning deviceaccording to the invention is given by the features of independent claim2. Advantageous refinements and developments are the subject matter ofthe dependent claims.

[0010] Accordingly, a first embodiment of the cushioning deviceaccording to the invention is distinguished in that the outer rotationalsleeve has, on its inner contour, an inwardly pointing inner stop andthe inner rotational part has, on its outer contour, an outwardlypointing counterstop which consists of soft material, reduction of theinner radius of the inner contour of the outer rotational sleeve in theregion in front of the inner stop enabling the outer contour of thecounterstop to come increasingly more strongly into contact with theinner wall of the outer rotational sleeve during rotation from the firstinto the second position, as a result of which first of all a brakingeffect is built up, and, when the counterstop strikes against the innerstop, the soft material of the counterstop enables a cushioning effectto be produced.

[0011] Accordingly, a second alternative refinement of the cushioningdevice according to the invention is distinguished in that the innerrotational part has, on its outer contour, an outwardly pointingcounterstop, and the outer rotational sleeve has, on its inner contour,an inwardly pointing inner stop which consists of a soft material,enlargement of the outer radius of the outer contour of the innerrotational part in the region in front of the counterstop enabling theouter contour of the inner stop to come increasingly more strongly intocontact with the outer wall of the inner rotational part during rotationfrom the first into the second position, as a result of which a brakingeffect is produced, and, when the inner stop strikes against thecounterstop, the soft material of the inner stop enables a cushioningeffect to be produced.

[0012] A braking and a cushioning effect can be reliably produced by thecushioning device according to the invention. The stop noise can bereliably suppressed. The braking effect used in front of the stop meansthat the components are treated carefully, which ensures reliablefunctioning in the long term with an increase in the service life of thecomponents.

[0013] A further advantage of the cushioning device according to theinvention resides in the fact that only two components are required inorder to produce the desired, advantageous effects, namely the outerrotational sleeve with its inner stop and the inner rotational part withits counterstop.

[0014] An advantageous refinement which ensures economical production isdistinguished in that the inner rotational part/the outer rotationalsleeve is designed as a two-component plastic part having aninjection-molded counterstop/inner stop made of soft material.

[0015] According to an advantageous development, the braking andcushioning effect is produced not only during pivoting from the firstinto the second position, but also the other way around when pivotingfrom the second position into the first position. This advantageousrefinement is distinguished in that there is a further inner stop on theinner contour of the outer rotational sleeve, in the region of whichstop the inner radius of the outer rotational sleeve is likewisereduced, with the result that the braking and cushioning effect isproduced during rotation from the second position into the firstposition.

[0016] A particularly advantageous refinement of the cushioning deviceaccording to the invention is characterized in that on the outer sidefacing the region in contact with the inner wall of the outer rotationalsleeve or the outer wall of the inner rotational part thecounterstop/the inner stop has a projecting contour which, during thefirst contact with the opposite wall, initially produces, as seen incross section, a point-shaped contact which becomes an extensive contactduring further rotation. By virtue of the fact that the projectingcontour which is selected enables the counterstop or the inner stopinitially only to come into contact in a pointwise manner with theopposite wall and to only come to an extensive contact during furtherrotation, the braking force is built up more or less continuously.

[0017] A particularly preferred development of the cushioning deviceaccording to the invention is distinguished in that a retainingprojection is integrally formed on the inner rotational part/on theouter rotational sleeve, which projection runs in the longitudinaldirection and has recesses in the form of a grid in the longitudinaldirection, and the counterstop/the inner stop is injection molded ontothis retaining projection. By virtue of the fact that there is anadditional retaining projection having recesses in the form of a grid, areliable connection in the long term of the injection-molded counterstopor of the injection-molded inner stop made of soft material is ensuredas a consequence of the form-fitting engagement.

[0018] As material for the soft counterstop or for the soft inner stop,use can be made, for example, of thermoplastic polyethylene (PE) orthermoplastic polyurethane (PU). Both the inner rotational part and theouter rotational sleeve are designed as plastic injection-molded parts.

[0019] A particularly advantageous refinement is distinguished in thatthe decrease of the inner diameter (R-R1) and the increase of the outerdiameter (R2-R3) of the outer rotational sleeve or of the innerrotational part has a linear profile.

[0020] Further embodiments and advantages of the invention are producedby the features also cited in the claims and also by the exemplaryembodiments specified below. The features of the claims can be combinedwith one another in any desired manner insofar as they obviously do noteliminate one another.

BRIEF DESCRIPTION OF THE DRAWING

[0021] The invention and advantageous embodiments and developmentsthereof will be described and explained in greater detail below withreference to the examples illustrated in the drawing. The features whichare to be gathered from the description and the drawing may, accordingto the invention, be used individually on their own or a number of themmay be used in any desired combination. In the drawing:

[0022]FIG. 1 shows a diagrammatic longitudinal section through acushioning device having an outer rotational sleeve and an innerrotational part, a counterstop made of soft material being present onthe inner rotational part and an inner stop being present on the outerrotational sleeve,

[0023]FIG. 2 shows a diagrammatic cross section through the cushioningdevice according to FIG. 1 in accordance with the sectional line A-Awith the outer rotational sleeve rotated into the functional position,

[0024]FIG. 3 shows a diagrammatic cross section through the cushioningdevice according to FIG. 1 in accordance with the sectional line A-A inthe stop position,

[0025]FIG. 4 shows a diagrammatic section through a cushioning deviceaccording to FIG. 1 supplemented by a further inner stop in a first stopposition,

[0026]FIG. 5 shows a diagrammatic cross section through the cushioningdevice according to FIG. 4 in a second stop position, and

[0027]FIG. 6 shows a diagrammatic cross section through a cushioningdevice with an inner rotational part and an outer rotational sleeve, theouter rotational sleeve having a soft inner stop and the innerrotational part having a counterstop.

WAYS OF IMPLEMENTING THE INVENTION

[0028] FIGS. 1 to 3 illustrate a cushioning device 10 which is used on afolding handle on the roof lining of a vehicle. The cushioning device 10has an essentially cylindrical outer rotational sleeve 14 which ispresent in a manner such that it can rotate about an axis of rotation16. Within the outer rotational sleeve 14 there is an inner rotationalpart 12 which is likewise designed as an essentially cylindrical sleeve.The inner rotational part 12 is pushed onto a bolt 18 which is mountedon a bearing bracket 36. At the same time, the inner rotational part 12is connected fixedly to the bearing bracket 36. In FIG. 1, the bearingbracket 36 is shown only by way of indication.

[0029] The outer rotational sleeve 14 is connected in a rotationallyfixed manner via an outer projection 22 to the handle strap 24 of afolding handle. The handle strap 24 is only indicated diagrammaticallyin fig.1. By means of the connection to the outer rotational sleeve 14,the handle strap 24 of the folding handle is present in a manner suchthat it can rotate about the axis 16.

[0030] An inwardly pointing inner stop 20 is integrally formed on theouter rotational sleeve 14. The outer rotational sleeve 14 is designedas a plastic injection-molded part, polyamide (PA) being selected as thematerial in the exemplary embodiment.

[0031] The inner rotational part 12 has a counterstop 26 which isintegrally formed on the outer contour. This counterstop 26 is made ofsoft plastic material, for example thermoplastic polyethylene (PE) orthermoplastic polyurethane (PU). In principle, a material havingelastomeric properties is possible. In the region of the counterstop 26,a retaining projection 30 having recesses 32 present in the form of agrid in the longitudinal direction is integrally formed on the innerrotational part 12 and the counterstop 26 is injection molded aroundsaid retaining projection. This additionally results in a form-fittingengagement of the injection-molded counterstop 26 with the retainingprojection 30, which ensures reliable functioning in the long term.

[0032] In addition, there is a projecting contour 28 on that outer sideof the counterstop 26 which faces the inner wall of the outer rotationalsleeve 14.

[0033] The inner wall of the outer rotational sleeve 14 has a radius Rin wide parts. In the region in front of the inner stop 20—as seenanticlockwise (see FIGS. 2 and 3)—the radius R decreases linearly to avalue R1 directly in front of the inner stop 20. The radius R isdimensioned in such a manner that the counterstop 26 does not come intocontact in this region with the inner wall of the outer rotationalsleeve 14.

[0034]FIG. 2 illustrates the cushioning device in a first position inwhich the counterstop 26 is not in contact with the inner wall of theouter rotational sleeve 14. If the outer rotational sleeve 14 is thenpivoted back anticlockwise (arrow D) as a consequence of the handlestrap 24 of the folding handle being pivoted back owing to a spring (notillustrated), then at the beginning of the region B with a reducedradius of the inner wall of the outer rotational sleeve 14 theprojecting contour 28, as seen in cross section, initially comes intocontact in a point-shaped manner with the inner wall of the outerrotational sleeve 14. The first braking effect already arises here. Withincreasing further rotation, the contact surface between the counterstop26 of the inner rotational part 12 and the inner wall of the outerrotational sleeve 14 becomes more extensive, as a result of which thebraking force is further increased. Finally, the counterstop 26 andinner stop 20 strike against each other, in which case the soft materialof the counterstop 26 and the braking effect which has previouslyoccurred enable striking noise to be suppressed and, taken as a whole,no great forces have to be absorbed during the striking itself, whichincreases the service life of the components.

[0035] A great advantage of the cushioning device illustrated is thefact that only two components, namely the inner rotational part 12 andthe outer rotational sleeve 14, have to be fitted in order to provide acushioning device which has a reliable braking and cushioning effect.

[0036]FIGS. 4 and 5 illustrate a further exemplary embodiment of acushioning device 10.1. This cushioning device 10.1 is largely identicalwith the cushioning device 10. Identical components bear the samereference number and will not be explained again. One difference overthe cushioning device 10 is that in the case of this selected exemplaryembodiment, the inner rotational part 12 is present in a rotatablemanner and the outer rotational sleeve 14 is present in a rotationallyfixed manner. A further difference is also the fact that there is afurther inner stop 34 virtually opposite the inner stop 20, after whichfurther inner stop a further region B1 is present, as seen clockwise,with a reduced radius of the inner wall of the outer rotational sleeve14. In the case of this exemplary embodiment, the braking and cushioningeffect is produced both when pivoting from the first into the secondposition and from the second into the first position.

[0037]FIG. 6 illustrates a further exemplary embodiment of a cushioningdevice 40. The latter has an essentially cylindrical outer rotationalsleeve 44, within which there is an essentially cylindrical innerrotational part 42. The two components are present about a common axisof rotation 16. The inner rotational part 42 is arranged on a bolt 18.

[0038] The outer rotational sleeve 44 furthermore has an outwardlypointing outer projection 22 for the form-fitting fastening to arotational part (not illustrated in greater detail). The innerrotational part 42 is connected fixedly, for example, to a bearingbracket (not illustrated) of the rotational part.

[0039] A counterstop 48 is integrally formed on the outer contour of theinner rotational part 42. The inner rotational part 42 largely has anidentical outer diameter R2. In the region in front of the counterstop48—as seen clockwise—the outer diameter is designed such that it iscontinuously enlarged from the size R2 to the size R3. The innerrotational part 42 is designed as a plastic injection-molded part.

[0040] An inner stop 46 made of soft plastic material is injectionmolded onto the inner wall of the outer rotational sleeve 44. The outerrotational sleeve 44 is also designed as an injection-molded plasticcomponent. The inner stop 46 corresponds in terms of its designessentially to the counterstop 26 from the cushioning device 10. It isdesigned in such a manner that it does not come into contact with theouter contour of the inner rotational part 42 in the radius region R2.In the region having an enlarged outer diameter (reference symbol C),the inner stop 46 comes increasingly more strongly into contact with theouter wall of the inner rotational part 42, as a result of which abraking effect occurs during a rotational movement D which is present.In the end position, the inner stop 46 comes into contact with thecounterstop 48, the soft material used for the inner stop 46 enabling acushioning effect to be produced when striking occurs.

[0041] The region B or C can be present in a circumferential region ofless than 45° (degrees).

[0042] The exemplary embodiments show cushioning devices for pivotableroof grab handles. However, the cushioning device can also be usedwithout any problem for other pivotable components, such as, forexample, sun vizors, covers for compartments accommodating spectacles orthe like.

1. A cushioning device for rotatable components, such as, for example,roof grab handles or sun vizors of a vehicle, having an outer rotationalsleeve, an inner rotational part, which are both arranged in a mannersuch that they can rotate relative to each other about a common axis ofrotation from a first rotational position into a second rotationalposition, either the inner rotational part being fixed and the outerrotational sleeve being rotatable or the outer rotational sleeve beingfixed and the inner rotational part being rotatable, characterized inthat the outer rotational sleeve has, on its inner contour, an inwardlypointing inner stop, the inner rotational part has, on its outercontour, an outwardly pointing counterstop which consists of softmaterial, reduction of the inner radius of the inner contour of theouter rotational sleeve in the region in front of the inner stopenabling the outer contour of the counterstop to come increasingly morestrongly into contact with the inner wall of the outer rotational sleeveduring rotation from the first into the second position, s a result ofwhich first of all a braking effect is built up, and, when thecounterstop strikes against the inner stop, the soft material of thecounterstop enables a cushioning effect to be produced.
 2. A cushioningdevice for rotatable components, such as, for example, roof grab handlesor sun vizors of a vehicle, having an outer rotational sleeve, an innerrotational part, which are both arranged in a manner such that they canrotate relative to each other about a common axis from a firstrotational position into a second rotational position, either the innerrotational part being fixed and the outer rotational sleeve beingrotatable or the outer rotational sleeve being fixed and the innerrotational part being rotatable, and the inner rotational part having aregion with increasing enlargement of the outer radius, characterized inthat the inner rotational part has, on its outer contour, an outwardlypointing counterstop, the outer rotational sleeve has, on its innercontour, an inwardly pointing inner stop which consists of a softmaterial, enlargement of the outer radius of the outer contour of theinner rotational part in the region in front of the counterstop enablingthe outer contour of the inner stop to come increasingly more stronglyinto contact with the outer wall of the inner rotational part duringrotation from the first into the second position, as a result of which abraking effect is produced, and, when the inner stop strikes against thecounterstop, the soft material of the inner stop enables a cushioningeffect to be produced.
 3. The cushioning device as claimed in claim 1 or2, characterized in that the inner rotational part/the outer rotationalsleeve is designed as a two-component plastic part having aninjection-molded counterstop/inner stop made of soft material.
 4. Thecushioning device as claimed in claim 1 or 2, characterized in thatthere is a further inner stop on the inner contour of the outerrotational sleeve, in the region of which stop the inner radius of theouter rotational sleeve is likewise reduced, with the result that thebraking and cushioning effect is produced during rotation from thesecond position into the first position.
 5. The cushioning device asclaimed in claim 1 or 2, characterized in that on the outer side facingthe region in contact with the inner wall of the outer rotational sleeveor the outer wall of the inner rotational sleeve or the outer wall ofthe inner rotational part the counterstop/the inner stop has aprojecting contour which, during the first contact with the oppositewall, initially produces, as seen in cross section, a point-shapedcontact which becomes an extensive contact during further rotation. 6.The cushioning device as claimed in claim 1 or 2, characterized in thata retaining projection is integrally formed on the inner rotationalpart/on the outer rotational sleeve, which projection runs in thelongitudinal direction and has recesses in the form of a grid in thelongitudinal direction, and the counterstop/the inner stop is injectionmolded onto this retaining projection.
 7. The cushioning device asclaimed in claim 1 or 2, characterized in that the inner rotationalpart/the outer rotational sleeve consists of polyamide and thecounterstop/inner stop consists of thermoplastic polyethylene orpolyurethane.
 8. The cushioning device as claimed in claim 1 or 2,characterized in that the inner rotational part is designed as an innerrotational sleeve which is pushed onto a bolt and which is fastened to abearing bracket of a rotatable component, in particular roof grabhandle, and the outer rotational sleeve is fastened to the rotatablecomponent.
 9. The cushioning device as claimed in claim 1 or 2,characterized in that the reduction of the inner diameter of the outerrotational sleeve and the increase of the outer diameter of the innerrotational part has a linear profile.
 10. The cushioning device asclaimed in claim 3, characterized in that there is a further inner stopon the inner contour of the outer rotational sleeve, in the region ofwhich stop the inner radius of the outer rotational sleeve is likewisereduced, with the result that the braking and cushioning effect isproduced during rotation from the second position into the firstposition.
 11. The cushioning device as claimed in claim 3, characterizedin that on the outer side facing the region in contact with the innerwall of the outer rotational sleeve or the outer wall of the innerrotational sleeve or the outer wall of the inner rotational part thecounterstop/the inner stop has a projecting contour which, during thefirst contact with the opposite wall, initially produces, as seen incross section, a point-shaped contact which becomes an extensive contactduring further rotation.